The NFL may have just been called out on its bluff. Dimopoulos Law Firm, reportedly the recipient of a cease-and-desist letter from the league last month, now appears to be suing the NFL first. Pro Football Talk’s Mike Florio broke the news this Thursday afternoon. The letter from the NFL – and subsequent lawsuit from Dimopoulous – stems from a commercial featuring Raiders defensive end Maxx Crosby. There were no NFL, Raiders or other protected trademarks or logos seen in the commercial, per PFT. A Las Vegas law firm has a commercial featuring Maxx Crosby in a silver and black…